MOLECULAR PUMP AND FLANGE

摘要

This invention is directed to the easy formation of an impact buffer structure. An impact buffer structure for consuming impact energy is provided in a molecular pump in its flange (61d). An insertion hole (40d) is provided in a flange. A buffer member (50d) formed of an independent small component is fitted into and fixed to the insertion hole. A bolt hole (14d) through which a bolt (65) is inserted is provided within the buffer member, for fixing the flange to a vacuum vessel. Thin-wall parts (82,83) are provided in the buffer member by forming hollow parts (72,73). Upon the occurrence of impact in a rotational direction of a rotor part in the molecular pump, for example, by breaking of the rotor part, the flange, together with the molecular pump, is slid in a rotational direction of the rotor part. This causes the bolt, through which the flange is fixed to the vacuum vessel in its flange to each other, hits against the buffer member resulting in plastic deformation of the buffer member. The plastic deformation of the buffer member consumes energy for molecular pump rotation and can buffer the impact generated in the molecular pump.